package shujvjiegou.week7;

import java.util.Scanner;

public class t4 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String str = scanner.next();
        String temp = "";
        int length = str.length();
        for (int i = 0; i < length / 2; ) {
            if (str.charAt(i) == str.charAt(length - i - 1)) {
                i++;
            } else {
                System.out.println("no");
                System.exit(0);
            }
        }
        System.out.println("yes");
    }
}
